1. Field of the Invention
This invention relates to a multi-unit electric welding apparatus, and, more particularly to an electric welding apparatus having a plurality of electric welding units, arranged in a row, which are supplied with welding current from a power source through a single welding transformer.
2. Description of Related Art
For space saving and low manufacturing cost, a plurality of welders, or electric welding units, are connected in parallel to a single welding transformer by means of electric conductors, or welding cables. If a plurality of electric welding units are arranged in a straight line, the welding cable must be longer as the distance of the electric welding unit from the welding transformer is. Accordingly, the welding cables have different electric resistances from one another and, hence, supply different welding work currents to the electric welding units. This results in non-uniform welding quality of works.